I connect to a database with read only access using SQL developer. It's a TNS connection. I use a tnsnames.ora, forwarding port script and SQL Developer.
In the past, occasionally, when connecting, I get a error message Got a minus one from a read call. Vendor Code 0
If I do a reboot, it goes away. Another friend suggested changed the forwarding port which worked for him.
I recently upgraded to a new computer and now it seems that I am getting the error message consistently. Reboot or changing forwarding port does not help at all.
The port forwarding script contains something like this
putty -L (port):(machine name):1521
Does anybody have any idea? Thanks.
My port forwarding script forwards multiple ports. Somehow separating them into 2 smaller file, this error went away.
Check your sqlnet.ora file and comment if there is any entry like the below.
tcp.validnode_checking = yes
tcp.invited_nodes=(<hostname_1>, <hostname_2>)
Now reload your listener and check the connectivity from SQL Developer.
lsnrctl reload <SID>
来源：https://stackoverflow.com/questions/2824438/got-a-minus-one-from-a-read-call